FIELD CROPS. 337 



average shrinkage of corn by months for the years 1903 to 1913, excepting 1904 

 and 1908, at Urbana, III., and the prices necessary each month to compensate 

 for shrinkage. 



The findings of the investigations are summarized as folloves : 



" Prices of farm crops in general are regulated by commercial market quota- 

 tions, which in turn are governed by supply and demand. The increase in prices 

 of crops within the last few decades has not been so great as many people have 

 believed. By comparing the average prices for the 15 years preceding the 

 financial crisis of 1894 to 1898 with the average prices for the 15 years suc- 

 ceeding this period, It will be seen that the average increase has been only 

 9.2 cts. per bushel for corn and 6.5 cts. for oats, while the average price for 

 wheat has not increased. The price for barley has tended to decrease, while 

 the price for rye has increased about the same as that for corn. 



In general for the last 30 years the times of lowest average price for corn, 

 wheat, and oats correspond closely to the times of largest average receipts. 

 Except during the summer months, the same is true for rye and also for barley 

 during the last ten years. 



" Shrinkage is one of the most important factors to be taken into consideration 

 in holding corn for higher prices. The total slu-inkage during the year is more 

 than 15 per cent. Taking November as a base, the data show that there is no 

 month for which the price increases sufficiently to compensate for shrinkage. 

 If January or February is taken as a base, then the increase in price up to 

 but not including October more than compensates for shrinkage alone. Not so 

 much is known of the shrinkage of wheat and oats as of corn. It may be said 

 that they shrink comparatively little after they have gone thoroughly through 

 the sweat. It would seem profitable, so far as shrinkage alone is concerned, 

 to hold small gi*ain until the time of highest prices." 



Crop rotation, R. T. Buedick {Vermont Sta. Bui. 190 (1915), pp. 440-460, 

 {•1^. 4)- — This article discusses the principles and practice of crop rotation. It 

 summarizes available data obtained at several experiment stations, suggests a 

 number of rotations, and presents a short bibliography. 



Concerning the corn crop, J. L. Hills (Vermont Sta. Bid. 189 (1915), pp. 

 S29-S80). — This article is of an informational character, compiled from many 

 sources, and treats of the origin and extent of the crop, varieties, corn breed- 

 ing, seed corn, climatic requirements, corn culture, and management of the crop, 

 pests, harvest, silos, shrinkage, corn judging, feeding, corn feeds, and school 

 lessons. 



A bibliography of U. S. Department of Agriculture and state experiment sta- 

 tion publications covering this field is appended. 



Development of the cotton plant under the influence of various fertilizers 

 and at different degrees of humidity of the soil. — Vegetation experiments in 

 1911 and 1912, R. Shreder (Izv. Turkest. Sclsk. Khoz. Opytn. Stantsli, 5 

 (1913) : abs. in Zhur. Opytn. Agron. (Russ. Jour. Expt. Landio.), 15 (1914), A'o. 

 5, pp. 386, 387). — In vegetation experiments conducted in 1903 and 1904 it was 

 found that only in the presence of sufficient moisture could the fertilizers intro- 

 duced exert their full influence, and that high humidity in conjunction with 

 nitrogenous and phosphatic fertilizers gave the highest yields. The data ob- 

 tained with reference to evaporation show that at any degree of humidity the 

 evaporation proceeded most economically under conditions of optimum nutri- 

 tion (nitrogen plus phosphorus). 



The experiments of 1911 showed that the best yields were obtained when 

 the humidity amounted to 60 per cent of the total capacity. 



The experiments with fertilizers in 1912 gave the following results: With 

 nitrate of soda and superphosphate the total yield doubled. With red clover as 



